Direct-current energized contactor



July 5- R. B. IMMEL ET AL 2,380,442

DIRECT-CURRENT ENERGI ZED CONTACTOR Filed July 20, 1943 2 Sheets-Sheet l WITNESSES: INVENTORS I Znvme/ and E6666 ZA'khfz/n M W.M

ATTORNEY Mr. I

July 31, 1945. R. B. IMMEL ET AL DIRECT-CURRENT ENERGIZED CONTACTOR Filed July 20, 1943 Z Sheets-Sheet 2 ATTORN EY Patented July 31, 1945 DIRECT-CURRENT ENERGIZED CONTACTOB Ralph B. Immel and Reese T. Kintzing, Wilkinsburg, Pa assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corpora.-

tion of Pennsylvania Application July 20, 1943, Serial No. 495,468

11 Claims.

This invention relates to direct-current enersized contactors, such as relays, switches and the like devices, in which a time delaying or timelimiting action is desired. and is related to the disclosure in the copending application Serial No. 495,487, filed July 20, 1943, by R. B. Immel, on "Adjustable time-limit devices."

It is an object of our invention to provide an electromagnetic time-limit device which afiords an adiustment and change in time limit with considerably greater ease than aflorded by the known devices of this type.

More specifically, in. this aspect, the invention aims at providing a type of electromagnetic contactor whose manuiacture and assembly can be substantially completed regardless oi the particular time limit to be obtained and can subseuently be adjusted to the specific time value without disassembly or reconstruction of the magnetic core structure and without separating the contactor body from its supporting frame or permanent circuit connections.

Another object in line with the foregoing is to permit a ready adjustment or change of the time limit bythe use! of thedevice, i. e. outside the factory or after the device has been installed in its ultimate place of operation.

While the invention involves using a selective plurality of short-circuited winding elements. it is also among its objects to render the time-limit adjustment more accurate and definitely predetel-mined than heretofore obtainable. In particular, a definite dependence of the time limit on the selected windings regardless of their speciile location along the core portion surrounded bythem,lslntended.

Y Still another object, in conjunction with any those aforementioned, is to facilitate the 'adlustment of the time limit to such an extent that the adiusiment can be carried out without the use or special tools or even without requiring any tools stall.

Lastly. also inconjunction with the foregoing. the invention aims at providing easily manipulsted means to: isstenin the short-circuited winding element in the proper place or remov- In order to achieve these objects, and in accordance with our invention, the mlimetizing winding of a time-limit device are arranged so that they surround appertaining magnet core with lufilcient play to form an interstice around ands-long the core, and a removable container orholderlsplaccdintothisinterstice and providodwithaselectivepluralityoisboit-circuitod mem er. isfi'rmly securedtothe armatur I,

winding elements, each surrounding the magnet core within the magnetizing coil when the container or holder is in its proper place. The time limit of such a device depends on the total resistance, cross section, or number of the inserted elements and is independent of their individual position along th core. An adjustment or change 01' the time limit can be effected with ease by-virtue of the fact that the winding elements are held together by this container or holder and hence can be'inserted or removed as a unit.

According to another feature of the invention, the above-mentioned container is provided with means, such as a spring clip, which serve as a handle when removing or inserting the container into the magnet coil and as a fastening device for maintaining the container in place after its insertion The foregoing objects and features will be apparent from the following description of the embodiment shown in the drawings.

Figure 1 is a top view of a timing relay according to the invention;

Figure 2 is a part-sectional side elevation;

Figure 3 a front elevation of the same relay;

Figs. 4 and 5 show separately the short-circuiting windin assembly oi the relay by a part-sectional side view and front view, respectively; and

Fig. 6 is a sectional view of part of another embodiment of the invention.

Referring to Figs. 1, 2 and 3. numeral I denotes a magnetizable supporting structure consisting, for instance, of an angular piece of iron. An elongated cylindrical magnet core Ills mounted on the support I and carries at one end a shim disc I and a pole piece 4, both attached to v the core 2 by memo: a riveted projection I formed by the core 2. The shim disc consists of a material of high'magnetic reluctance, for instance brass. The diameters of the shim I and of the pole piece 4 are equal to that or the core member 2 so that the entire core assembly has a straight cylindrical shape over the entire longitudinal extent of the assembly.

A magnetic armature t has its upper edge placed against the support i and is held in position by means or an abutment plate I which is firmly attached to the structure I. The upper edge of the armature I contacting the structure liscutinanacute angleinordertopermitthe armature O rotational movements about the inicrum formed by the armature edge. A bracket the idler end or this bracket. in the illustrated position. rests against a stationary abutment formed by a metal piece I which is mounted on the supporting structure I. This abutment piece limits the motion or the armature 6 in the direction away from the magnet core 2 and, as illustrated, may contain a screw for adjusting the inactive position or the armature.

A bolt a has itslower end journalied to the bracket member I and carries a helical spring ll whose lower end rests against a nut 21 engaging the bolt 20,;while the upper end or the spring ll abuts against the bracket member I. The bolt It carries a cross bar II which bridges a recess formed by the abutment plate I. The two ends of the cross bar are bent away at right angles and form lugs I! which engage corresponding openinss ll of the abutment plate I.

When the relay is in assembled condition as representedbyl'igsljandii, thespring II is under compression and hence pulls the cross bar ll against the abutment plate 1 thereby securing the lugs I! in their engagement with the openings it while holding the armature 8 and the bracket I in the position shown in Fig. 2, in which the bracket member s rests against the abutment member I. In this condition, the compressed springI ll biases the armature away from the core minals II and II, respectively. In the illustrated position, the contact member I4 is moved away from the stationary contacts I! and Il. When the armature is attracted by the magnet core l AsapparentfromI 'igs.2,4and5,atubularcontainer 10 is placed in the interstice between the magnet core and the magnetizing winding. The container has an annular-end wall II provided with a circumferential groove 32 which is engaged by a depressed portion of the cylindrical wall 30 and thus fastened to the cylindrical wall. Another front ring II having a circumferential groove I! is similarly attached to the other end of the cylinder wall II. The cylinder wall 80 has a cutout portion at a which extends over at least 180 of the periphery in order to permit the insertion and removal of a plurality of ringshaped shorbdrcuiting winding elements 22. In I embodiment, tour such rings 22 or theillustrated equal areprovidedtoiilltheentire axial length of the tubular container. The axial width of the opening 39 is slightly larger than that of the rings 22.

The tubular container Ill and its appertaining parts II and Ii as well as the rings 22 consist of an electrically good conductive material such as copper, although other conductive metals or alloys, such as iron or brass. may also be employed. The container and the rings placed therein form a short-circuiting current path around the magnet core 2 which extends entirely within the magnetizing winding It. The total electric resistance oi this current depends on the number of rings 22 placed into the container and hence can be adjusted by selecting a corresponding number 0! rings 22. The container II with its end portions ii and II is preferably so dimensioned that its total electric resistance is substantially equal to that of one winding element 2!. Consequently, the illustrated embodiment. requiring four rings 22 to completely fill the container 30, permits six diiferent adjustments of the time constant of the relay. The

minimum time constant is obtained when the relay is used without container and rings. A slight degree of retardation is adjusted by placing the container I. without rings into the magnetizing coil. A greatr delay results if the container is provided with a single ring I2, and so forth, the maximum time being obtained when four rings 22 are placed into the container. In this manner, in the embodiment constructed in accordance with Figs. 1 through 5, a range of time delays between approximately of a second up to 1% or almost up to 2 seconds could be obtained.

While the just-mentioned adjustment is limited to a number of definite retardation steps, the relay permits also a time adjustment to intermediate values by changing the force 0! spring ill with the aid of adjusting nut 11. In this manner, any desired time limit between the available minimum and maximum can be adjusted.

Due to the fact that all short-circuiting winding elements when properly inserted into the magnetizing coil I! lie within the axial length of the magnet core which is surrounded by the magnetizing coil, the location of the individual elements 2! within the container 80 has no noticeable eiiect on the adjusted time limit. For instance, it only one element 22 is inserted into the tubular container, the time limit remains the same whether the element lies next to the supporting structure for close to the armature O or in some intermediate position.

As shown in Figs. 4 and 5, a spring clip I4 is hinged to the front portion ll of the tubular container at II and II. The clip has a center portion 31 which is bent towards the magnet coil and, in the illustrated position of the clip, ongages a circumferential groove ll of the core structure. This engagement secures the tubular container and the winding elements housed therein in proper position relative to the coil and the core. By forcing the clip portion 81 out of the groove 38, the clip is disengaged and can then be used as a convenient handle for pulling the container out of the magnetizing coil when a change in time limit adjustment is necessary.

The modification illustrated in Pig. 6 refers to a timing relay which is desi ned in accordance with Figs. 1, 2 and 3, with the exception that the short-circulting winding elements and their holder are constructed in a manner diiiermt from the one represented by the preceding M- ures. According to Fig. 8. the holder II for the 2,3so,442 v 3 ring-shaped winding elements 22' consists of a tube which is removably placed over the magnet core 2 within the interstice between the core and the magnetizing coil is. The tube 30' has an exterior thread and the elements 22' form screw nuts and engage the thread. The elements 22' are preferably provided with bores 40 in order to facilitate threading them onto the tube 30' and for permitting an easy removal of the entire tube assembly from the magnetizing coil l9 by placing a wire through one or several bores 40 of the outermost element 22'. The minimum delay limit is obtained when only the tube 30 is placed mm the interstice and the maximum delay when the entire length of the tube 30' is covered with winding elements 22'.

Since, as shown by the above-described examples, our invention is capable of modification without departing from its spirit and scope, we wish this disclosure to be considered as illustrative and not in a limiting sense.

We claim as our invention:

1. In an electromagnetic time limit device, the combination of a magnetic core member, a magnetizing coil surrounding said member and forming a. peripheral interstice therewith, a container removably arranged in said interstice and surrounding said member within said coil, and a plurality of short-circuiting winding elements removablj, arranged in said container to permit changing the time limit of the device by a corresponding selection of said elements.

2. In an electromagnetic time limit device, the combination of a magnetic structure having a base member, an elongated core attached 'at one end to said base member and an armature linked to said base member opposite the other end of said core, a magnetizing coil disposed around said core and spaced therefrom to form a peripheral interstice, a container adapted to surround said core within said interstice and being removable from said core member towards saidother end, and a plurality of annular elements of electrically conductive material removably arranged in said container to permit adjusting the time limit of the device by a corresponding selection of said elements.

3. In an electromagnetic time limit device, the combination of a magnetic core member, a ma netizing coil surrounding said member and forming a peripheral interstice therewith, a container removably disposed in said interstice around said member and consisting of electrically conductive material so as to form a short circuiting winding element, and a plurality of electrically conductive annular elements removably arranged in said container to permit changing the time limit of the device by a corresponding selection of said elements. I

4. In an electromagnetic time limit device, the combination of a magnetic core member, a magnetizing coil surrounding said member and forming a peripheral interstice therewith, a container removably arranged in said interstice and surrounding said member within said coil, a plurality of short-circuiting winding elements removably arranged in said container to permit changing the time limit of the device by a corresponding selection of said elements, and an attachment hinged to said container for fastening it in proper position relative to said member and forming a handle for removing said container and elements from said interstice.

5. In an electromagnetic time limit device, the combination of a magnetic structure having a base member, an elongated core attached at one end to said base member and an armature linked to said base member opposite the other end of said core, said core having a recess at its periphery near said other end, a magnetizing coil disposed around said core and spaced therefrom to form'a peripheral interstice, a container disposed to'surround said core within said interstice and being removable from said core member towards said other end, and a plurality of annular elements of electrically conductive material removably arranged in said container to permit adjusting the time limit of the device by a corresponding selection of said elements, and a clip linked to said container so as to form a handle when removing said container and disposed to engage said recess for securing said container in proper position relative to said core when inserted into said interstice.

6. In an electromagnetic time limit device, the combination of a magnetic core member, a magnetizing coil surrounding said member and forming aperipheral interstice therewith, a container removably arranged in said interstice and sur-' rounding said member within said coil, a plurality of electrically conductive rings matching the peripheral dimensions of said container, said container having an opening at its peripheral surface for inserting said rings to permit changing the time limit of the device by a corresponding selection of said elements.

7. In an electromagnetic time limit device, the combination of a magnetic core member, a magnetizing coil surrounding said member and forming a peripheral interstice therewith, a container removably arranged in said interstice and surrounding said member within said coil, a plurality of rings dimensioned to be stacked over one another within said container, said container and said rings consisting of electrically conductive material and forming short-circuited winding elements of approximately equal delaying effect on the operation of the device so as to permit ad-.

justing the total time limit by a selection in number of said elements. v

8. In an electromagnetic time limit device, the combination of a magnetic structure having a core member, a magnetizing coil surrounding said member so as to form a peripheral interstice therewith, said coil being firmly secured to said structure soas to be supported independently of said core member, a plurality of short-circuited winding elements disposed to be removably inserted into said interstice for surrounding said member within said coil, and holding means engaging said elements for removin them together in order to vary the time limit of the device by a corresponding selection of said element.

9. In an electromagnetic time limit devlce, the combination of a magnetic core member, a magnetizing coil surrounding said member so as to form a peripheral interstice therewith, a plurality of electrically conductive rings disposed to be removably inserted into said interstice for surrounding said member within said coil, and a holding device for engaging said rings to permit creasing the time limit of the relay, said winding having a cylindric container of electrically conductive material removably surrounding said core, and a plurality of electrically conductive annular elements movably arranged in said container for permitting an adjustment of the relay time constant by a corresponding insertion and removal respectively of said elements from said container.

11. In combination with a magnetic core of a timing relay, a short circuited winding for increasing the time limit of th relay, said winding having a container of electrically conductive material removably surrounding said core, and a plurality of electrically conductive annular elements movably arranged in said container for permitting an adjustment of the relay time constant by a corresponding insertion and removal respectively of said elements from said container, having annular end walls and an opening in its peripheral wall, and electrically conductive rings matching the peripheral dimensions of said con tainer and the longitudinal width of said opening to be placed into said container through said opening for adjustin the time limit by selecting the number of the inserted rings.

, RALPH B. IMMEL.

REESE T. KIN'IZING. 

